To fill a gap between warped configurations of a semiconductor module and a cooler for the purpose of improving heat dissipation properties, a conventional semiconductor device has a structure in which a grease member is provided in a filling region between the semiconductor module such as a T-PM (Transfer mold Power Module) and the cooler and in which the semiconductor module is pressed down and fixed using a plate and the like from the opposite side of the semiconductor module from the cooler while the grease member is caused to interfere. Such a structure of the semiconductor device is disclosed, for example, in Patent Literature 1.